Centaurea sphaerocephala, L.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1976, Flora Europaea. Volume 4. Plantaginaceae to Compositae (and Rubiaceae), Cambridge University Press : 283

152. C. sphaerocephala L. , Sp. Pl. 916 (1753).

Perennial. Stems 5-70 cm, procumbent to erect, simple or branched, leafy up to capitulum, not winged. Leaves spinulose-mucronate, hispidulous to arachnoid-tomentose, viscid; lower usually lyrate; upper usually entire or dentate, sometimes auriculate-semiamplexicaul. Capitula solitary; involucre 12-35 mm in diameter; bracts not distinctly veined; appendages reddish-brown, deflexed, with 5-13 slender spines 3-5 mm, the apical usually somewhat longer. Florets purple or sometimes the inner whitish, the outer patent. Achenes c. 5 mm, shiny; pappus absent in outer and short in inner achenes. Sandy ground, mainly by the sea. W. Mediterranean region, Portugal. Co?Cr?Gr Hs It Lu Sa Si.

1 Stems up to 60 cm, corymbosely branched; involucre 8-20 mm

in diameter, the appendages with yellowish-orange spines

(b) subsp. lusitanica 1 Stems 5-30 cm; simple or sparingly branched; involucre (15-)

20-35 mm in diameter, the appendages with yellow spines 2 Stems 5-15 cm; involucre 30-35 mm in diameter, truncate at base (d) subsp. polyacantha 2 Stems 10-30 cm; involucre c. 20 mm in diameter, rounded at base 3 Leaves arachnoid-hairy, mucronate-dentate

(a) subsp. sphaerocephala 3 Leaves tomentose, somewhat viscid, spiny-dentate

(c) subsp. malacitana